The Official Pattern Release or OPR is Trend Micro's latest compilation of patterns for identified viruses. Trend Micro offers various types of Pattern Files to protect customers from Malware, Spyware/Grayware, and other threats... It is guaranteed to have passed a series of critical tests to ensure that customers get optimum protection from the latest virus threats. Use this version of the pattern file for all Trend Micro products running on Intel or DEC Alpha based operating systems and for products using Trend's virus scanning API Library. Because more than 200 new viruses are discovered every month, it is strongly suggested that you update your virus pattern files regularly. This pattern file is most effective when used with the latest scan engine. We strongly encourage you to update your scan engine to ensure you are using the best virus protection available.